title: Nasal bone and trisomy 21: prenatal ultrasound and postmortem morphohistological study.
mesh_terms: D001344:Autopsy; D004314:Down Syndrome / Q000000981:diagnostic imaging*; D005260:Female; D005865:Gestational Age; D006801:Humans; D009295:Nasal Bone / Q000002:abnormalities*; D011247:Pregnancy; D016216:Ultrasonography, Prenatal / Q000379:methods